hi everyone,

i have study maple for many days .now i have two questions about DAE with bvp probelem . maple 11 doesn't seem to solve the problems.the two problems are similar.

the question one is :

k1'(t)= -1              (1)      

k1(t)-2*a(t)*k2(t)=0       (2)

a(t)=v'(t)                 (3 )    

j(t)=a'(t)                （4）              

m-a^2(t)-g^2(t)=0          (5)       

g(t)*k2(t)=0               (6)

n+k2(t1)(m^2-g^2(t1))=0     (7)

the boundary is：v(0)=0    v(t1)=p(constant )    a(0)=0  a(t1)=0

where,  k1(t),k2(t),a(t),g(t),j(t),v(t) is fucntion of "t" ，t  range :0-t1 ,t1 is unkown ,m,n, p are known constant .

the question two  is :

x1’(t)=x2(t)       x1(t0)=x0                

x2’ (t)=u(t)          x2(t0)=v0       t0 ,tf ,x0,v0 ,v1  are kown constant 

k1’(t)=0            k1(tf)= -1      

k2’(t)=-k1(t)         x2(tf)=v1          

z(t)*k3(t)=0            

k2(t)=k3(t)[2*u(t)-u1-u2]             

z(t)*z(t)=[u(t)-u2]*[u1-u(t)]           u2<=u(t)<=u1    u1, u2 are kown constant 

where,  k1(t),k2(t),k3(t),z(t),u(t),x1(t),x2(t) is fucntion of "t" ，t  range :t0-t1 , t0 ,tf ,x0,v0 ,v1 ,u1, u2  are known constant 。

i have study many days but fail to solve ,can you give some help to solve them with numeric method?

contact me :meimeila123@sina.com    thank you !

any help or comment i will bi appreciated!